deps: Upgrade packages to latest, namely app_settings and image_picker

This is the result of `flutter pub upgrade --major-versions`.

Changelogs:
  https://pub.dev/packages/app_settings/changelog
  https://pub.dev/packages/image_picker/changelog

The API changes don't affect our usage.

pubspec.lock

@@ -29,10 +29,10 @@ packages:
     dependency: "direct main"
     description:
       name: app_settings
-      sha256: "34c6b7dbf493d486b082f9538ea11b2ee665e7125618660555d5415592e78667"
+      sha256: "67ca58aba6ec311d89597c2716d2e37da54b8c7cef28b7749e6551c57f88c1f4"
       url: "https://pub.dev"
     source: hosted
-    version: "4.3.0"
+    version: "5.0.0"
   args:
     dependency: transitive
     description:
@@ -436,10 +436,10 @@ packages:
     dependency: "direct main"
     description:
       name: image_picker
-      sha256: b6951e25b795d053a6ba03af5f710069c99349de9341af95155d52665cb4607c
+      sha256: b9603755b35253ccfad4be0762bb74d5e8bf9ff75edebf0ac3beec24fac1c5b5
       url: "https://pub.dev"
     source: hosted
-    version: "0.8.9"
+    version: "1.0.0"
   image_picker_android:
     dependency: transitive
     description:

pubspec.yaml

@@ -52,8 +52,8 @@ dependencies:
   path_provider: ^2.0.13
   path: ^1.8.3
   sqlite3_flutter_libs: ^0.5.13
-  app_settings: ^4.2.0
-  image_picker: ^0.8.7+3
+  app_settings: ^5.0.0
+  image_picker: ^1.0.0
   package_info_plus: ^4.0.1
   collection: ^1.17.2
   url_launcher: ^6.1.11